/**
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */

package com.aelitis.azureus.util;

import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.bouncycastle.util.encoders.Base64;
import org.gudy.azureus2.core3.util.Debug;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.JSONValue;

/**
 * @author TuxPaper
 * @created Feb 14, 2007
 * 
 */
public class JSONUtils {
    /**
     * decodes JSON formatted text into a map.
     * 
     * @return Map parsed from a JSON formatted string
     *         <p>
     *         If the json text is not a map, a map with the key "value" will be returned. the value of "value" will either be an List, String,
     *         Number, Boolean, or null
     *         <p>
     *         if the String is formatted badly, null is returned
     */
    public static Map decodeJSON(String json) {
        try {
            Object object = JSONValue.parse(json);
            if (object instanceof Map) {
                return (Map) object;
            }
            // could be : ArrayList, String, Number, Boolean
            Map map = new HashMap();
            map.put("value", object);
            return map;
        } catch (Throwable t) {
            Debug.out("Warning: Bad JSON String: " + json, t);
            return null;
        }
    }

    /**
     * encodes a map into a JSONObject.
     * <P>
     * It's recommended that you use {@link #encodeToJSON(Map)} instead
     * 
     * @param map
     * @return
     * 
     * @since 3.0.1.5
     */
    public static JSONObject encodeToJSONObject(Map map) {
        JSONObject newMap = new JSONObject((int) (map.size() * 1.5));

        for (Map.Entry<String, Object> entry : ((Map<String, Object>) map).entrySet()) {
            String key = entry.getKey();
            Object value = entry.getValue();

            if (value instanceof byte[]) {
                key += ".B64";
                value = Base64.encode((byte[]) value);
            }

            value = coerce(value);

            newMap.put(key, value);
        }
        return newMap;
    }

    /**
     * Encodes a map into a JSON formatted string.
     * <p>
     * Handles multiple layers of Maps and Lists. Handls String, Number, Boolean, and null values.
     * 
     * @param map
     *            Map to change into a JSON formatted string
     * @return JSON formatted string
     * 
     * @since 3.0.1.5
     */
    public static String encodeToJSON(Map map) {
        JSONObject jobj = encodeToJSONObject(map);
        StringBuilder sb = new StringBuilder(8192);
        jobj.toString(sb);
        return (sb.toString());
    }

    public static String encodeToJSON(Collection list) {
        return encodeToJSONArray(list).toString();
    }

    private static Object coerce(Object value) {
        if (value instanceof Map) {
            value = encodeToJSONObject((Map) value);
        } else if (value instanceof List) {
            value = encodeToJSONArray((List) value);
        } else if (value instanceof Object[]) {
            Object[] array = (Object[]) value;
            value = encodeToJSONArray(Arrays.asList(array));
        } else if (value instanceof byte[]) {
            try {
                value = new String((byte[]) value, "utf-8");
            } catch (UnsupportedEncodingException e) {
            }
        }
        return value;
    }

    /**
     * @param value
     * @return
     * 
     * @since 3.0.1.5
     */
    private static JSONArray encodeToJSONArray(Collection list) {
        JSONArray newList = new JSONArray(list.size());

        for (Object value : list) {

            newList.add(coerce(value));
        }

        return newList;
    }

    public static void main(String[] args) {

        Map mapBefore = new HashMap();
        byte[] b = { 0, 1, 2 };
        mapBefore.put("Hi", b);
        String jsonByteArray = JSONUtils.encodeToJSON(mapBefore);
        System.out.println(jsonByteArray);
        Map mapAfter = JSONUtils.decodeJSON(jsonByteArray);
        b = MapUtils.getMapByteArray(mapAfter, "Hi", null);
        System.out.println(b.length);
        for (int i = 0; i < b.length; i++) {
            byte c = b[i];
            System.out.println("--" + c);
        }

        Map map = new HashMap();
        map.put("Test", "TestValue");
        Map map2 = new HashMap();
        map2.put("Test2", "test2value");
        map.put("TestMap", map2);

        List list = new ArrayList();
        list.add(new Long(5));
        list.add("five");
        map2.put("ListTest", list);

        Map map3 = new HashMap();
        map3.put("Test3", "test3value");
        list.add(map3);

        System.out.println(encodeToJSON(map));
        System.out.println(encodeToJSON(list));
    }
}
